short URLs for blog posts using s42.ca

An htaccess file is generated that redirects the
short URL to blog posts.

.gitignore

@@ -5,3 +5,4 @@ discussd/discuss.dirty
 public/blog
 public/proj
 node_modules
+public/s42/.htaccess

Makefile

@@ -29,6 +29,7 @@ publish_blog: blog publish_assets
 	./bin/publish.sh --delete public/blog
 	scp public/blog/posts.json bohodev.net:discussd/posts.json
 	scp discussd/discussd.js bohodev.net:discussd/discussd.js
+	scp public/s42/.htaccess samhuri.net:s42.ca/.htaccess
 	ssh bohodev.net restart-discussd.sh
 
 publish_proj: proj publish_assets

bin/blog.rb

@@ -11,6 +11,9 @@ require 'rdiscount'
 
 DefaultKeywords = ['sjs', 'sami samhuri', 'sami', 'samhuri', 'samhuri.net', 'blog']
 
+ShortURLCodeSet = '0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ'
+ShortURLBase = ShortURLCodeSet.length.to_f
+
 def main
   srcdir = ARGV.shift.to_s
   destdir = ARGV.shift.to_s
@@ -49,6 +52,7 @@ class Blag
     generate_rss
     generate_posts_json
     generate_archive
+    generate_short_urls
     copy_assets
   end
 
@@ -101,6 +105,17 @@ class Blag
     File.open(rss_file, 'w') { |f| f.puts(rss_for_posts.target!) }
   end
 
+  def generate_short_urls
+    htaccess = ['RewriteEngine on', 'RewriteRule ^$ http://samhuri.net [R=301,L]']
+    posts.reverse.each_with_index do |post, i|
+      code = shorten(i + 1)
+      htaccess << "RewriteRule ^#{code}$ #{post[:url]} [R=301,L]"
+    end
+    File.open(File.join(@dest, 's4,', '.htaccess'), 'w') do |f|
+      f.puts(htaccess)
+    end
+  end
+
   def copy_assets
     Dir[File.join(@src, 'css', '*.css')].each do |stylesheet|
       `yui-compressor #{stylesheet} #{File.join(@css_dest, File.basename(stylesheet).sub('.css', '.min.css'))}`
@@ -223,6 +238,15 @@ class Blag
     xml
   end
 
+  def shorten(n)
+    short = ''
+    while n > 0
+      short = ShortURLCodeSet[n % ShortURLBase, 1] + short
+      n = (n / ShortURLBase).floor
+    end
+    short
+  end
+
 end
 
 main if $0 == __FILE__